The invention relates to systems and circuits including measurement of parameters of electronic components, especially to measurement of the effective series resistance of a capacitor.
In many applications information about the effective series resistance of a capacitor is necessary to provide robust function. So called “energy reserve capacitors” are often employed to provide an autonomous power supply, especially in security-relevant automotive applications such as, for example, airbag control systems, where energy reserve capacitors play a vital role in the case the battery is disconnected. Furthermore, in some systems the power for firing the squibs in order to deploy the airbags comes exclusively from the energy reserve capacitor. Since the current consumption may be 2 A or more, a significant voltage drop may be generated across the effective series resistance of the energy reserve capacitor. This voltage drop may have a negative impact on the robustness and the functionality of the respective integrated circuit.
To allow for adequate provisions to avoid the negative effects of the voltage drop across the effective series resistance of the capacitor, a measurement of the effective resistance may be necessary. For these and other reasons, there is a need for the present invention.